Method and apparatus for video encoding and/or decoding to prevent start code confusion

Abstract

A method and a video processor for preventing start code confusion. The method includes aligning bytes of a slice header relating to slice data when the slice header is not byte aligned or inserting differential data at the end of the slice header before the slice data when the slice header is byte aligned, performing emulation prevention byte insertion on the slice header, and combine the slice header and the slice data after performing emulation prevention byte insertion.

What is claimed is: 
     
       1. A method comprising:
 receiving an encoded bitstream representing a slice, the slice comprising a slice header and slice data; 
 removing an emulation prevention byte from the encoded bitstream, wherein a first portion of the emulation prevention byte occurs in the slice header, and wherein a second portion of the emulation prevention byte occurs in the slice data; 
 extracting slice-header information from the slice header for the slice in the encoded bitstream, the slice-header information comprising sample adaptive offset information; 
 after extracting the slice-header information from the slice header for the slice, performing byte alignment at an end of the slice header; and 
 after performing byte alignment at the end of the slice header, extracting slice-data information from the slice data for the slice from the encoded bitstream. 
 
     
     
       2. The method of  claim 1 , wherein performing byte alignment comprises extracting a stop bit from the encoded bitstream. 
     
     
       3. The method of  claim 2 , wherein the stop bit represents a binary value of one. 
     
     
       4. The method of  claim 3 , wherein performing byte alignment further comprises extracting at least one byte alignment bit from the encoded bitstream after extracting the stop bit from the encoded bitstream. 
     
     
       5. The method of  claim 4 , wherein the at least one byte alignment bit represents a binary value of, zero. 
     
     
       6. The method of  claim 1 , further comprising performing a second byte alignment at an end of the slice data after extracting data in the slice data for the slice. 
     
     
       7. The method of  claim 1 , wherein the first portion of the emulation prevention byte occurs at an end of the slice header. 
     
     
       8. The method of  claim 1 , wherein the first portion of the emulation prevention byte includes a final two bytes of the slice header. 
     
     
       9. The method of  claim 1 , wherein the second portion of the emulation prevention byte occurs at a beginning of the slice data. 
     
     
       10. The method of  claim 1 , wherein the second portion of the emulation prevention byte includes an initial four bytes of the slice data. 
     
     
       11. A system comprising:
 a receiver configured to receive an encoded bitstream representing a slice, the slice comprising a slice header and slice data; 
 a decoder coupled to the receiver and configured to:
 remove an emulation prevention byte from the encoded bitstream, wherein a first portion of the emulation prevention byte occurs in the slice header, and wherein a second portion of the emulation prevention byte occurs in the slice data; 
 extract slice-header information from the slice header for the slice in the encoded bitstream, the slice-header information comprising sample adaptive offset information; 
 after extracting the slice-header information from the slice header for the slice, perform byte alignment at an end of the slice header; and 
 after performing byte alignment at the end of the slice header, extract slice-data information from the slice data for the slice from the encoded bitstream. 
 
 
     
     
       12. The system of  claim 11 , wherein performing byte alignment comprises extracting a stop bit from the encoded bitstream. 
     
     
       13. The system of  claim 12  wherein the stop bit represents a binary value of one. 
     
     
       14. The system of  claim 13 , wherein performing byte alignment further comprises extracting at least one byte alignment bit from the encoded bitstream after extracting the stop bit from the encoded bitstream. 
     
     
       15. The system of  claim 14 , wherein the at least one byte alignment bit represents a binary value of zero. 
     
     
       16. The system of  claim 11 , further comprising performing a second byte alignment at an end of the slice data after extracting data in the slice data for the slice. 
     
     
       17. The system of  claim 11 , wherein the first portion of the emulation prevention byte occurs at an end of the slice header. 
     
     
       18. The system of  claim 11 , wherein the first portion of the emulation prevention byte includes a final two bytes of the slice header. 
     
     
       19. The system of  claim 11 , wherein the second portion of the emulation prevention byte occurs at a beginning of the slice data. 
     
     
       20. The system of  claim 11 , wherein the second portion of the emulation prevention byte includes an initial four bytes of the slice data.